You can use any small yoghurt bottles for this game. If you don’t have any carton bottles, you can use plastic bottles like Actimel bottles.
Anyway you need to wash the bottles before you give them to your dog.
I took 9 of these carton bottles and I put about 5-15 kibble in each. It took Miki about 7 minutes to get all the kibble out.
Later on I put 20 yoghurt bottles into a small cardboard box. First I put some small treats on the bottom of the box and also one treat in each bottle, before I placed the bottles into the box.
It took Miki 10 minutes to get all the treats out.
I also tried this game by taping five of these bottles side by side. This game was too easy for Miki; the treats were eaten in about 10 to 15 seconds.